The study has been conducted by researchers at Bispebjerg University Hospital who surveyed over 15,000 twins living in Denmark and asked them to fill out a questionnaire that included questions based on presence of asthma and on fertility. The researchers then divided them into groups based on whether or not they had asthma and if they had, whether they had received any treatment. The participants were also asked whether they had been trying to get pregnant for longer than a year without success and how many children they had given birth to.
The researchers found that around 27 percent of those from the asthma group reported on taking prolonged time before getting pregnant compared to just 21.6 percent of non-asthmatics, while the time taken was longer among women who had not been treated for their condition. The study has been published in the European Respiratory Journal.
"Our results shed light on the complex interactions between fertility and asthma. Although we observed women with asthma experiencing longer waiting times to pregnancy, our findings suggest that if women take their medication and control their asthma, they can reduce this delay. As the negative effect of asthma on fertility is reduced by treatment, we can assume that the systemic inflammation characterized by asthma may account for the effect on delaying fertility", lead researcher Dr Elisabeth Juul Gade said.